Originally Posted by Tub
select your GPU / Monitor and set the GPU Scaling Method to "Centered" or "Aspect Ratio Scaled".
I think too, that this applies only to DVI connected devices. I don't have that setting in nvidia-settings, and when I tried to set FlatpanelProperties in xorg.conf, it didn't do anything.
But it's understandable. My Screen ist connected via VGA so it gets discovered as a "CRT". A "DFP" ("Digital Flat Panel") is connected via DVI.